Senior Member

You are correct with respect to "développement"; my mistake. If you are replying to a former supervisor, I would then suggest to use the polite form i.e. "Je vais m'efforcer de vous garder au fait de tout nouveau développement"

Senior Member

if it has to be polite, "vous" should be used.
And "je vous tiendrai au courant de l'évolution de la situation etc" is very polite.
Or "=========== informé ==================== " is even more polite.
"garder au fait" is right, but a bit precious

Senior Member

if it has to be polite, "vous" should be used.
And "je vous tiendrai au courant de l'évolution de la situation etc" is very polite.
Or "=========== informé ==================== " is even more polite.
"garder au fait" is right, but a bit precious